First off, theres already been like at least 3 other big threads about this same topic. Second, I believe your right. It fits everything. And it would make sense for him to come back and try to end the lives of people who did damage to him.

And as of right now, the only theories I think are plausible are:1: It's Xehanort's Something or other!2: It's Xehanort!3: It's a whole new character!4: It's an older Ventus! (Though this is still fairly new and somewhat fragile with it's bases.)

You know, me and a friend the other day said that the final boss of the final game (KH3 its looking like) would be Sora, since deep down he just wanted to live a normal live, so he tried to change everything so he never got the Keyblade.

Then shit happens and 'Current' Sora accepts his position and they fight etc etc etc.

And as of right now, the only theories I think are plausible are: 1: It's Xehanort's Something or other! 2: It's Xehanort! 3: It's a whole new character! 4: It's an older Ventus! (Though this is still fairly new and somewhat fragile with it's bases.)